# NAME

BusyBox - The Swiss Army Knife of Embedded Linux

# SYNTAX

     busybox <applet> [arguments...]  # or

     <applet> [arguments...]          # if symlinked

# DESCRIPTION

BusyBox combines tiny versions of many common UNIX utilities into a single small executable. It provides minimalist replacements for most of the utilities you usually find in GNU coreutils, util-linux, etc. The utilities in BusyBox generally have fewer options than their full-featured GNU cousins; however, the options that are included provide the expected functionality and behave very much like their GNU counterparts.

BusyBox has been written with size-optimization and limited resources in mind. It is also extremely modular so you can easily include or exclude commands (or features) at compile time. This makes it easy to customize your embedded systems. To create a working system, just add /dev, /etc, and a Linux kernel. BusyBox provides a fairly complete POSIX environment for any small or embedded system.

BusyBox is extremely configurable. This allows you to include only the components you need, thereby reducing binary size. Run 'make config' or 'make menuconfig' to select the functionality that you wish to enable. Then run 'make' to compile BusyBox using your configuration.

After the compile has finished, you should use 'make install' to install BusyBox. This will install the 'bin/busybox' binary, in the target directory specified by CONFIG_PREFIX. CONFIG_PREFIX can be set when configuring BusyBox, or you can specify an alternative location at install time (i.e., with a command line like 'make CONFIG_PREFIX=/tmp/foo install'). If you enabled any applet installation scheme (either as symlinks or hardlinks), these will also be installed in the location pointed to by CONFIG_PREFIX.

# USAGE

BusyBox is a multi-call binary. A multi-call binary is an executable program that performs the same job as more than one utility program. That means there is just a single BusyBox binary, but that single binary acts like a large number of utilities. This allows BusyBox to be smaller since all the built-in utility programs (we call them applets) can share code for many common operations.

You can also invoke BusyBox by issuing a command as an argument on the command line. For example, entering

            /bin/busybox ls

will also cause BusyBox to behave as 'ls'.

Of course, adding '/bin/busybox' into every command would be painful. So most people will invoke BusyBox using links to the BusyBox binary.

For example, entering

            ln -s /bin/busybox ls
            ./ls

will cause BusyBox to behave as 'ls' (if the 'ls' command has been compiled into BusyBox). Generally speaking, you should never need to make all these links yourself, as the BusyBox build system will do this for you when you run the 'make install' command.

If you invoke BusyBox with no arguments, it will provide you with a list of the applets that have been compiled into your BusyBox binary.

# COMMON OPTIONS

Most BusyBox applets support the --help argument to provide a terse runtime description of their behavior. If the CONFIG_FEATURE_VERBOSE_USAGE option has been enabled, more detailed usage information will also be available.

# COMMANDS

Currently available applets include:

            ash, awk, basename, blkid, brctl, cat, chmod, chown, chroot, cmp,
            cp, date, dd, df, dhcprelay, dirname, dmesg, du, echo, egrep, env,
            expr, fdisk, fgrep, find, free, grep, halt, hd, hexdump, hostid,
            hostname, hwclock, id, ifconfig, init, insmod, install, kill,
            killall, klogd, less, link, linuxrc, ln, logger, login, logname, ls,
            lsmod, lsof, lsusb, mdev, mesg, mkdir, mkdosfs, mkfs.vfat, mknod,
            modprobe, more, mount, mountpoint, mv, pidof, ping, pivot_root,
            poweroff, printenv, printf, ps, pstree, pwd, reboot, rm, rmdir,
            rmmod, route, sh, sleep, sort, start-stop-daemon, sync, sysctl,
            syslogd, telnet, telnetd, tftp, top, touch, udhcpc, udhcpd, uevent,
            umount, uptime, vi, watch, wget, xargs

# COMMAND DESCRIPTIONS

ash

  ash [-/+OPTIONS] [-/+o OPT]... [-c 'SCRIPT' [ARG0 [ARGS]] / FILE [ARGS]]

awk

  awk [OPTIONS] [AWK_PROGRAM] [FILE]...

basename

  basename FILE [SUFFIX]

blkid

  blkid [BLOCKDEV]...

brctl

  brctl COMMAND [BRIDGE [INTERFACE]]

cat

  cat [-nbvteA] [FILE]...

chmod

  chmod [-R] MODE[,MODE]... FILE...

chown

  chown [-Rh]... USER[:[GRP]] FILE...

chroot

  chroot NEWROOT [PROG ARGS]

cmp

  cmp [-l] [-s] FILE1 [FILE2]

cp

  cp [OPTIONS] SOURCE... DEST

date

  date [OPTIONS] [+FMT] [TIME]

dd

  dd [if=FILE] [of=FILE] [ibs=N] [obs=N] [bs=N] [count=N] [skip=N] [seek=N] [conv=notrunc|noerror|sync|fsync] [iflag=skip_bytes]

df

  df [-PkmhT] [FILESYSTEM]...

dhcprelay

  dhcprelay CLIENT_IFACE[,CLIENT_IFACE2]... SERVER_IFACE [SERVER_IP]

dirname

  dirname FILENAME

dmesg

  dmesg [-c] [-n LEVEL] [-s SIZE]

du

  du [-aHLdclsxhmk] [FILE]...

echo

  echo [-neE] [ARG]...

env

  env [-iu] [-] [name=value]... [PROG ARGS]

expr

  expr EXPRESSION

fdisk

  fdisk [-ul] [-C CYLINDERS] [-H HEADS] [-S SECTORS] [-b SSZ] DISK

find

  find [-HL] [PATH]... [OPTIONS] [ACTIONS]

free

  free

grep

  grep [-HhnlLoqvsriwFE] [-m N] [-A/B/C N] PATTERN/-e PATTERN.../-f FILE [FILE]...

halt

  halt [-d DELAY] [-n] [-f]

hd

  hd FILE...

hexdump

  hexdump [-bcCdefnosvx] [FILE]...

hostid

  hostid

hostname

  hostname [OPTIONS] [HOSTNAME | -F FILE]

hwclock

  hwclock [-r|--show] [-s|--hctosys] [-w|--systohc] [-t|--systz] [-l|--localtime] [-u|--utc] [-f|--rtc FILE]

id

  id [OPTIONS] [USER]

ifconfig

  ifconfig [-a] interface [address]

init

  init

insmod

  insmod FILE [SYMBOL=VALUE]...

install

  install [-cdDsp] [-o USER] [-g GRP] [-m MODE] [-t DIR] [SOURCE]... DEST

kill

  kill [-l] [-SIG] PID...

killall

  killall [-l] [-q] [-SIG] PROCESS_NAME...

klogd

  klogd [-c N] [-n]

less

  less [-EIMmNSh~] [FILE]...

link

  link FILE LINK

ln

  ln [OPTIONS] TARGET... LINK|DIR

logger

  logger [OPTIONS] [MESSAGE]

login

  login [-p] [-h HOST] [[-f] USER]

logname

  logname

ls

  ls [-1AaCxdLHRFplinshrSXvctu] [-w WIDTH] [FILE]...

lsmod

  lsmod

lsof

  lsof

mdev

  mdev [-s]

mesg

  mesg [y|n]

mkdir

  mkdir [OPTIONS] DIRECTORY...

mkdosfs

  mkdosfs [-v] [-n LABEL] BLOCKDEV [KBYTES]

mkfs.vfat

  mkfs.vfat [-v] [-n LABEL] BLOCKDEV [KBYTES]

mknod

  mknod [-m MODE] NAME TYPE MAJOR MINOR

modprobe

  modprobe [-alrqvsD] MODULE [SYMBOL=VALUE]...

more

  more [FILE]...

mount

  mount [OPTIONS] [-o OPT] DEVICE NODE

mountpoint

  mountpoint [-q] <[-dn] DIR | -x DEVICE>

mv

  mv [-fin] SOURCE DEST or: mv [-fin] SOURCE... DIRECTORY

pidof

  pidof [OPTIONS] [NAME]...

ping

  ping [OPTIONS] HOST

pivot_root

  pivot_root NEW_ROOT PUT_OLD

poweroff

  poweroff [-d DELAY] [-n] [-f]

printenv

  printenv [VARIABLE]...

printf

  printf FORMAT [ARG]...

ps

  ps

pstree

  pstree [-p] [PID|USER]

pwd

  pwd

reboot

  reboot [-d DELAY] [-n] [-f]

rm

  rm [-irf] FILE...

rmdir

  rmdir [OPTIONS] DIRECTORY...

rmmod

  rmmod [-wfa] [MODULE]...

route

  route [{add|del|delete}]

sh

  sh [-/+OPTIONS] [-/+o OPT]... [-c 'SCRIPT' [ARG0 [ARGS]] / FILE [ARGS]]

sleep

  sleep [N]...

sort

  sort [-nrugMcszbdfiokt] [-o FILE] [-k start[.offset][opts][,end[.offset][opts]] [-t CHAR] [FILE]...

start-stop-daemon

  start-stop-daemon [OPTIONS] [-S|-K] ... [-- ARGS...]

sync

  sync

sysctl

  sysctl [OPTIONS] [KEY[=VALUE]]...

syslogd

  syslogd [OPTIONS]

telnet

  telnet [-a] [-l USER] HOST [PORT]

telnetd

  telnetd [OPTIONS]

tftp

  tftp [OPTIONS] HOST [PORT]

top

  top [-b] [-nCOUNT] [-dSECONDS] [-m]

touch

  touch [-c] FILE...

udhcpc

  udhcpc [-fbqRB] [-a[MSEC]] [-t N] [-T SEC] [-A SEC/-n] [-i IFACE] [-s PROG] [-p PIDFILE] [-oC] [-r IP] [-V VENDOR] [-F NAME] [-x OPT:VAL]... [-O OPT]...

udhcpd

  udhcpd [-fS] [-I ADDR] [CONFFILE]

uevent

  uevent [PROG [ARGS]]

umount

  umount [OPTIONS] FILESYSTEM|DIRECTORY

uptime

  uptime

vi

  vi [OPTIONS] [FILE]...

watch

  watch [-n SEC] [-t] PROG ARGS

wget

  wget [-c|--continue] [--spider] [-q|--quiet] [-O|--output-document FILE] [--header 'header: value'] [-Y|--proxy on/off] [-P DIR] [-S|--server-response] [-U|--user-agent AGENT] [-T SEC] URL...

xargs

  xargs [OPTIONS] [PROG ARGS]

# LIBC NSS

GNU Libc (glibc) uses the Name Service Switch (NSS) to configure the behavior of the C library for the local environment, and to configure how it reads system data, such as passwords and group information. This is implemented using an /etc/nsswitch.conf configuration file, and using one or more of the /lib/libnss_* libraries. BusyBox tries to avoid using any libc calls that make use of NSS. Some applets however, such as login and su, will use libc functions that require NSS.

If you enable CONFIG_USE_BB_PWD_GRP, BusyBox will use internal functions to directly access the /etc/passwd, /etc/group, and /etc/shadow files without using NSS. This may allow you to run your system without the need for installing any of the NSS configuration files and libraries.

When used with glibc, the BusyBox 'networking' applets will similarly require that you install at least some of the glibc NSS stuff (in particular, /etc/nsswitch.conf, /lib/libnss_dns*, /lib/libnss_files*, and /lib/libresolv*).

Shameless Plug: As an alternative, one could use a C library such as uClibc. In addition to making your system significantly smaller, uClibc does not require the use of any NSS support files or libraries.

# MAINTAINER

Denis Vlasenko <vda.linux@googlemail.com>

# AUTHORS

The following people have contributed code to BusyBox whether they know it or not. If you have written code included in BusyBox, you should probably be listed here so you can obtain your bit of eternal glory. If you should be listed here, or the description of what you have done needs more detail, or is incorrect, please send in an update.

Emanuele Aina <emanuele.aina@tiscali.it> run-parts

Erik Andersen <andersen@codepoet.org>

        Tons of new stuff, major rewrite of most of the
        core apps, tons of new apps as noted in header files.
        Lots of tedious effort writing these boring docs that
        nobody is going to actually read.

Laurence Anderson <l.d.anderson@warwick.ac.uk>

        rpm2cpio, unzip, get_header_cpio, read_gz interface, rpm

Jeff Angielski <jeff@theptrgroup.com>

        ftpput, ftpget

Edward Betts <edward@debian.org>

        expr, hostid, logname, whoami

John Beppu <beppu@codepoet.org>

        du, nslookup, sort

Brian Candler <B.Candler@pobox.com>

        tiny-ls(ls)

Randolph Chung <tausq@debian.org>

        fbset, ping, hostname

Dave Cinege <dcinege@psychosis.com>

        more(v2), makedevs, dutmp, modularization, auto links file,
        various fixes, Linux Router Project maintenance

Jordan Crouse <jordan@cosmicpenguin.net>

        ipcalc

Magnus Damm <damm@opensource.se>

        tftp client insmod powerpc support

Larry Doolittle <ldoolitt@recycle.lbl.gov>

        pristine source directory compilation, lots of patches and fixes.

Glenn Engel <glenne@engel.org>

        httpd

Gennady Feldman <gfeldman@gena01.com>

        Sysklogd (single threaded syslogd, IPC Circular buffer support,
        logread), various fixes.

Karl M. Hegbloom <karlheg@debian.org>

        cp_mv.c, the test suite, various fixes to utility.c, &c.

Daniel Jacobowitz <dan@debian.org>

        mktemp.c

Matt Kraai <kraai@alumni.cmu.edu>

        documentation, bugfixes, test suite

Stephan Linz <linz@li-pro.net>

        ipcalc, Red Hat equivalence

John Lombardo <john@deltanet.com>

        tr

Glenn McGrath <bug1@iinet.net.au>

        Common unarchiving code and unarchiving applets, ifupdown, ftpgetput,
        nameif, sed, patch, fold, install, uudecode.
        Various bugfixes, review and apply numerous patches.

Manuel Novoa III <mjn3@codepoet.org>

        cat, head, mkfifo, mknod, rmdir, sleep, tee, tty, uniq, usleep, wc, yes,
        mesg, vconfig, make_directory, parse_mode, dirname, mode_string,
        get_last_path_component, simplify_path, and a number trivial libbb routines

        also bug fixes, partial rewrites, and size optimizations in
        ash, basename, cal, cmp, cp, df, du, echo, env, ln, logname, md5sum, mkdir,
        mv, realpath, rm, sort, tail, touch, uname, watch, arith, human_readable,
        interface, dutmp, ifconfig, route

Vladimir Oleynik <dzo@simtreas.ru>

        cmdedit; xargs(current), httpd(current);
        ports: ash, crond, fdisk, inetd, stty, traceroute, top;
        locale, various fixes
        and irreconcilable critic of everything not perfect.

Bruce Perens <bruce@pixar.com>

        Original author of BusyBox in 1995, 1996. Some of his code can
        still be found hiding here and there...

Tim Riker <Tim@Rikers.org>

        bug fixes, member of fan club

Kent Robotti <robotti@metconnect.com>

        reset, tons and tons of bug reports and patches.

Chip Rosenthal <chip@unicom.com>, <crosenth@covad.com>

        wget - Contributed by permission of Covad Communications

Pavel Roskin <proski@gnu.org>

        Lots of bugs fixes and patches.

Gyepi Sam <gyepi@praxis-sw.com>

        Remote logging feature for syslogd

Linus Torvalds <torvalds@transmeta.com>

        mkswap, fsck.minix, mkfs.minix

Mark Whitley <markw@codepoet.org>

        grep, sed, cut, xargs(previous),
        style-guide, new-applet-HOWTO, bug fixes, etc.

Charles P. Wright <cpwright@villagenet.com>

        gzip, mini-netcat(nc)

Enrique Zanardi <ezanardi@ull.es>

        tarcat (since removed), loadkmap, various fixes, Debian maintenance

Tito Ragusa <farmatito@tiscali.it>

        devfsd and size optimizations in strings, openvt and deallocvt.

Paul Fox <pgf@foxharp.boston.ma.us>

        vi editing mode for ash, various other patches/fixes

Roberto A. Foglietta <me@roberto.foglietta.name>

        port: dnsd

Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>

        misc

Mike Frysinger <vapier@gentoo.org>

        initial e2fsprogs, printenv, setarch, sum, misc

Jie Zhang <jie.zhang@analog.com>

        fixed two bugs in msh and hush (exitcode of killed processes)